Water heater



Feb. 28, 1933. E AQ. w. OTT r AL.

WATER HEATER Filed Jan. 25, 19:51l

Patented Feb. 28, 1933 nutren sr'rss remi oFFicE CRAN W'. OTT, 0F LOS ANGELES, AND ARTER SMITHERS, OF ALHAMBRA, CALI'- FORNIA, ASSIGNORS-TO PACIFIC PIPE AND ,SUPPLY COMIEANY,l OF 'LOSQNG'ELES;V CALIFORNIA, A COBIPORATION OF CALIFORNIA l WATER, HEATER y This invention relates to water heaters vand particularly to domestic water vheaters. "In localities where the water contains lime compounds thereis considerable difficulty in operating heaters, particularly heaters of the coil type because of the deposit of sulphate or carbonateof lime on the interiorof Vthe coil. rl'Chis deposit or scale materially Vinter-V feres with the efficiency of the heater in transferring heat to the service water being heated and also materially reduces the effective cross section of the coil, thereby diminishing the amount of wat-er that can flow through the heating coil for delivery at the point where the hot wateris to be used. found that the deposits from hard water are greatly increased` with lthe temperature of the plate or surface that is heating the water. In other words, a considerable deposit occurs where a iiame or hot gases are located on 'one side of the heating wall and the water being heated is in contact with the other side of the heating wall.

It has been attempted to overcome these diiculties by constructing a heater with trapped `water which comes in contact with the wall that is highly heated by the lire and this trapped water is utilized as a ytransfer medium fortransferring the heat to the service water. In this way the deposit of lime or similar compoundsin the service water chamber is greatly reduced. However, if the trapped water is completely confined it may develop a considerable pressure and thisV would necessitate a substantial increase in the thickness of the plates confining the trapped water.

The general object of this invention is to provide a heater of simple construction which will overcome these diiculties and which is particularly adapted for'heating hard waters; also to provide a heater of this type which will be highly eficient in. operation and which is so constructed as to maintain equilibrium between the pressure of thev trapped water and the service water chamber in which the service water is being heated but without necessitating a constant change in the trapped water. In other words, water is substantially trapped and is substantially It has beeny free fromreplacementbyfthe servicel water.

In this way the deposits in the trapping chamber are greatly reduced.

A. further lob 'ect ofthe invention is to provide a heater which can be constructed at alow cost which will be eflicient intrans; ferring heat to the service water butin which the deposits from the hard water willbe re? duced toa minimum. f Further objects of pear hereinafter.

The invention consists in novel partsV and the invariata; willV ap# combinations of partsto be described hereinafter, all of which contribute to'producer an efficient water heater.'

A. preferred embodiment of the invention is described in the following specification, whilethe broad scope of the 'invention is pointed outin the appended claims. l

In the drawing: A Figure 1 is a vertical section through la heater embodying our invention with certain parts broken away. `4

Figure'Q is ay horizontal V section taken about on the line 2-2 of Figure 1. Y

Referring lmoreparticularly tothe parts,

in constructing theheater we provide a shell 1 preferably of cylindrical form in an upright position, the lower endof the said shell being utilized to form a .fire boi; Q-'provided vwith seY meansfor developing heat, foreXample, a gas burner 3.V The upper side ofthe fire box 2 is nearly closedbya lire boxhead 4, with a i central openingY carrying a flue 5 preferably f,

of tubular form that extends upwardly and passes throughthe upper head 6 ofthe shell 1. -Over the fire box head 4 is a water head? whichis formed witha central opening carrying a tubular jacket 8 that surrounds the flue 5 and cooperates with the ysameto form an annular relatively narrow water 'jacket 9 is formedbetween the heads i and 7 The metal and crowned in an upward Vdirectionlso' communica-ting with thewater space 10v that i Y that their convex sides are disposed upward- Y lv.- rhey are yformed with flanges 11 thatV The tubular jacket 8 extendsup' toianelemay be welded tothe inner side of the shell l.Y

I secured to the flue just below the head 6.

Preferably at an elevated point so as to be remote from the ebullition point in the heater we provide means of communication between the water jacket space 9 and the service water space 13 that is formed within the shell 1 and around the jacket 8. This may be accomplished in any suitable manner but we prefer to employ for this purpose an opening 14 formed in the jacket just below the jacket head 12 (see Fig. 1). This opening should not be so largek as to permit circulation between the trapped water space and the space. 13. Ve prefer to provide the iiue 5k with means for increasing thel temperature and transfer of heat at as low a point in the heater as possible. v For this purpose we preferv to provide the interior of the flue 5 With a plurality of baffles 15 which may be of general fan shape (see Figure 2) and carried yon a common central rod or stem 16.

If desired the shell 1 maybe surrounded with lagging 17 of insulating material forming an insulating jacket between the shell 1 and an outer covering or shell A18. The heater may be provided with a sleeve 19 for the attachment of a thermostat control device.

In the operation of this' heater it will be .evident that although the opening 1a lprevents any possibility of developing a higher pressure in the trap compartment 9 than in the service water compartment 13, nevertheless, the water in the trapped water compartment is substantially trapped, that is to say, theV construction is such as to prevent free circulation between the trapped water compartment and the service compartment. Of course, if boiling occurs in thetr'apped water there is a tendency for a slight emission of water to occur at theV opening 14 intothey upper part of the chamber V13,but` in this operation the battles `15 cooperate to4 confine the highest temperature to a low level in the flue. In -this wa hot water rising in the jacket space 9 ten sto have its temperature reduced before it reaches the opening 14. If any slight emission of water does occur from the jacket space 9, a replacement of this water would occur but such replacements are in Vsuch small quantities that they do not substantially increase the deposit of lime compoundsin the trapped water space. The head 6 is' provided with nipples 20 and 21, one of which would be an inlet and the other an outlet for the heated service water.

What we claim is: Y

1. In a water heater of the kind described, the combination of a shell having a service water chamber for the service water to be heated, a Water inletr and a water outlet therefor, a irebox with a head in the lower part of lthe Sheik-a hot gas flue extending up from the said head for carrying up gasesof combustion from the ire-box, a water head mounted 1n.

the shell above the tire-box head and cooper'- ating with the fire-box head and the shell to form a trapped water compartment over the fire-box head, a tubular jacket surrounding the said flue and connected to the water head so as to form a trapped water jacket around the flue communicating with the said water compartment, a cover head secured to the said shell, and means located remote from the ebullition point adjacent said lire-box head, for maintaining pressure communicationbetween the water jacket and the service water space within the said shell and operating toy maintain equilibrium of pressures without circulation of water between the trapped-water in the jacket and the service water being heated in the water space of the shell, said pressure communicating means being the sole means of communication between the water jacket and the service water compartment. j s Y 2 In acwater heater of the kinddescribed, thecombination of a shell having a service water chamber for the service water to be heated, a water inlet and a water outlet therefore, a tire box with a fire-box head in the lower part of the shell, a hot gas flue extending up from the said head for carrying up gases of combustionr from the tire-box, a lwater head mounted inthe shell above the lire-box head and cooperating with the lireboX head and the shell toform a trapped water compartment over the fire-box head', a tubular jacket surrounding the said l'lue and connected to the water head so as to form. a trapped water jacket around the flue communicating with the said water compartment, a cover head secured to the said shell with a restricted opening remote from ther ebullij tion point at said lire-box head and adjacent the upper end ofthe tubular jacket and operating to maintain equilibrium of pressure without circulation between the water in the jacket and the water space of the shell, said pressure communicating means being the sole means of communication betweenthe water lire-box head and cooperating with the fireboX head Vand the shell to form a trapped water compartment over the lire-box head, a

vconnected to the water Vhead lso as to form a 'ico point of said lire-box head, for maintaining pressure equalization between the water jacket and the service water space within the said shell and operating to maintain equilibrium of pressure without circulation between the trapped water in the jacket and the service water being heated inthe water space of the shell, said pressure communicating means being the sole means of communication between the water jacket and the service water compartment, said heater head and said water head being of crowned form with the convex side disposed upwardly and having iianges at their edges secured to said shell.

4. Tn a water heater of the kind described, the combination of a shell having a service water chamber for the service water to'be heated, a fire-box with a fire-box head in thel lower part of the shell, a Hue extending up from the said head for carrying up gasesof combustion from the fire-box, awater head jacket and the service water space within the mounted in the shell above the lire-box head and cooperating with the hre-box head and the shell to form a trapped water compartment over the hre-box head, a tubular jacket l surrounding the said iiue and connected to the water head so as to form a trapped water jacket around the iiue communicating with the said water compartment, a cover head secured to the said shell, and means located at a high level within the shell for maintaining j communication between the water jacket and the service water space within the said shell and operating to maintain equilibrium of pressures between the trapped water in the jacket and the service water being heated in the water space of the shell, said heater head and said water head being of crowned form with the convexside disposed upwardly and having flanges at ltheir edges secured to said shell, and baiiies carried within the flue for checking the outward .flow of the gases of combustion, thereby increasing the temperaf' ture toward the lower part of the flue and jacket, and reducing the temperature of the trapped water in the upper part of the jacket.

5. In a water heater of the kind described, the combination of a shell having a service water chamber for the service water to be heated, a water inlet and a water outlet therefor, a head in the lower part of the shell, a

lue extending up from the head for carrying up a heating gas, a water head mounted i in the shell above the first named head and cooperating with the first named head and the shell to form a trapped water compartment over the first named head, aY tubular jacket surrounding the said flue and connected to the water head so as to form a trapped water jacket around the flue communicating with the said water compartment, a cover head secured to the said shell, and means located on the jacket for maintaining pressure communication between the water lOO 

